The invention relates to a printer which feeds continuous feed paper sheets through the printer by means of edge strips which are formed on opposite sides of the paper sheets. Such printers range from very expensive, high speed line printers to very inexpensive printers sold primarily for small business and home use. Such printers use paper which is in a continuous length, but with spaced-apart, laterally-extending perforation lines. The paper can be separated into individual sheets when desired by tearing along the perforation line.
According to the applicant's pending U.S. patent application, Ser. No. 947,751, filed on Sep. 21, 1992, the paper sheets are automatically separated by using a particular length of continuous-feed paper. The length of continuous-feed paper includes pre-separated sheets of paper attached solely by edge strips located on opposite side edges of the paper. As the edge strips are removed, the paper sheets separate and become disconnected from the continuous length.
The edge strips are separable from the paper sheets by means of perforation lines which extend along the length of the paper sheets. The perforation lines define the edge strip and paper sheets on opposite sides thereof. The edge strips have holes which extend along its length at regularly spaced-apart intervals which match the spacing of sprocket teeth on the axially-extending peripheral surface of sprocket wheels which are positioned on opposite sides of the printer at the paper platen.
The edge strips are usually manually torn from the paper sheets after the paper has been removed from the printer. This is a tedious, time consuming job. For this reason, those trimming the edge strips manually tend to try to remove the edge strips from a number of sheets at the same time by fan folding the sheets, if they are not already fan folded. If too many layers are stripped at the same time, the edge strip can fail to separate cleanly, and can either leave a ragged remnant of the edge strip attached to the paper sheet, or can tear into the paper sheet, thereby requiring that sheet to be re-printed.
The invention of this application relates to an improved edge strip trimmer for particular use with a length of continuous-feed paper according to the applicant's pending U.S. patent application, Ser. No. 947,751. Since this particular length of continuous-feed paper does not include laterally-extending perforation lines for attaching the top and bottom edges of the paper sheet to adjacent sheets, the top and bottom edges of the sheet tend to sag when passed through the printer and respective edge strip trimmers. This creates a problem, since each sheet must pass over a support bed of the edge strip trimmer to be separated from its edge strip. If the top or bottom edge of the sheet sags, the sheet may pass under instead of over the support bed of the trimmer. Thus, the edge strip will not be trimmed, and the sheets will not be properly separated.
The edge strip trimmer of the present application eliminates this problem by proving an lengthened and curved support bed for ensuring that each sheet of paper is properly fed through the edge strip trimmers.